The impact of domestic and foreign trade on energy-related PM emissions in Beijing

Particulate matter (PM) adversely affects air quality, human health and the climate, and it is more prevalent in urban areas. Few efforts have been made to quantify the impact of trade on PM concentrations in an urban economy. This paper presents an analysis of the impacts of domestic and international trade on PM emissions in Beijing using a three-scale input–output model, supported by the national and global embodied energy-related PM2.5, PM10 and TSP (total suspended particulate) emission intensities. The results found that the total energy-related PM2.5, PM10 and TSP emissions (production-based) in Beijing were 106Gg, 163Gg and 347Gg, respectively, in 2010. Of these amounts, 48% (51Gg, 74Gg and 146Gg, respectively) was associated with local demand, 42% (44Gg, 73Gg and 168Gg, respectively) was associated with domestic exports, and 10% (11Gg, 16Gg and 33Gg, respectively) was associated with international exports. From a consumption perspective, Beijing’s PM2.5, PM10 and TSP emissions were more than double the production-based PM emissions. Approximately 75% (172Gg, 311Gg and 786Gg, respectively) of the consumption-based PM emissions were domestically outsourced to other provinces, primarily via the import of metal (32Gg, 58Gg and 151Gg), construction (26Gg, 36Gg and 91Gg) and chemical products (16Gg, 30Gg and 75Gg), and 3% (8Gg, 10Gg and 24Gg, respectively) of consumption-based PM emissions were outsourced abroad. Our results indicate that domestic trade plays a dominant role in Beijing’s PM2.5 emissions. These findings suggest that more national and sub-national government should co-ordinate design and implement effective mechanisms to alleviate urban air pollution because of the significant effects of interprovincial and international trade on local emissions.